sbo
usfromempeemp_bo
usebwhereeemp
oebemp
oa
dedept
o10groupbydept
o
十八、从多个表中返回丢失的数据db2mysqlpostgresqlsqlserverselectddept
odd
ameee
amefromdeptdfullouterjoi
empeo
ddept
oedept
oselectddept
odd
ameee
amefromdeptdrightouterjoi
empeo
ddept
oedept
ou
io
selectddept
odd
ameee
amefromdeptdleftouterjoi
empeo
ddept
oedept
ooracleselectddept
odd
ameee
amefromdeptdempewhereddept
oedept
ou
io
selectddept
odd
ameee
amefromdeptdempewhereddept
oedept
o十九、在运算和比较时使用
ull值selecte
amecommfromempwherecoalescecomm0selectcommfromempwheree
ameWARD
二十、从一个表向另外的表中复制行i
serti
todept_eastdept
od
amelocselectdept
od
amelocfromdeptwhereloci
NEWYORKBOSTON
二十一、复制表定义db2createtabledept_2likedeptoraclemysqlpostgresqlcreatetabledept_2asselectfromdeptwhere10sqlserverselecti
todept_2fromdeptwhere10
二十二、一次向多个表中插入记录oraclei
sertallwhe
loci
NEWYORKBOSTONthe
i
todept_eastdept
od
amelocvaluesdept
od
amelocwhe
locCHICAGOthe
i
todept_middept
od
ameloc
fvaluesdept
od
amelocelsei
todept_westdept
od
amelocvaluesdept
od
amelocselectdept
od
amelocfromdeptdb2i
serti
toselectfromdept_westu
io
allselectfromdept_eastu
io
allselectfromdept_midselectfromdeptmysqlpostgresqlsqlserver不支持多表插入操作
二十三、阻止对某几列插入在表中创建一个视图，该视图将只显示允许用户进行操作的列，强制所有的插入操作都通过该视图进行createview
ew_empsasselectemp
oe
amejobfromemp
二十四、用其他表中的值更新db2mysqlupdateempesetesalecommselect
ssal
ssal2from
ew_sal
swhere
sdept
oedept
owhereexistsselect
ulfrom
ew_sa
swhere
sdept
oedept
ooracleupdateselectesalasemp_salecommasemp_comm
ssalas
s_sal
ssal2as
s_commfrmempe
ew_sal
swhereedept
o
sdept
osetemp_sal
s_salemp_comm
s_commpostgresqlupdateempsetsal
ssalcomm
ssal2from
ew_sal
swhere
sdept
oempdept
osqlserverupdateesetesal
ssalecomm
ssal2fromempe
ew_sal
swhere
sdept
oempdept
o
二十五、合并记录oraclemergei
toemp_commissio
ecusi
gselectfromempempo
ecemp
oempemp
owhe
matchedthe
updateseteccomm1000deletewheresal2000whe
otmatchedthe
i
sertecemp
oece
ameecdept
oeccommvaluesempemp
oempe
ameempdept
oempcomm
f二十六、删除违反参照完整性的记录deletefromempwhere
otexistsselectfromdeptwheredeptdept
oempdept
odeletefromempwheredept
o
oti
selectdept
ofromdept
二十七、删除重复记录deletefromdupeswhereid
oti
ser
